Could the tags be made using ceramics?
The microchip in an RFID transponder is composed of silicon. The antenna can be made of etched copper, aluminum or conductive ink, while the chip and antenna are typically put on a substrate that is PET or paper. Usually, this inlay is inserted into a printable label to create an RFID transponder that can be affixed to a product.
Throughout the years, RFID transponders have been used for many different applications, so transponders have been embedded in hard plastic to protect them. Some have been embedded in ceramic to protect them from heat (see New On-Metal UHF Tag Measures Just 5 Millimeters in Length and HID Global Intros Ceramic Brick and Slimflex On-Metal Tags). There are also tags that can be embedded in metal (see Armored-RFID Tag Loves to Get Hammered).
—Mark Roberti, Founder and Editor, RFID Journal